package com.mycat.common.util.encryption.aes;
import java.security.SecureRandom;

import javax.crypto.Cipher;
import javax.crypto.KeyGenerator;
import javax.crypto.spec.SecretKeySpec;

import sun.misc.BASE64Decoder;
import sun.misc.BASE64Encoder;
  
/**
 *	AES加解密
 * @author Roger
 */
@SuppressWarnings("restriction")
public class AESUtil {  
      
    public static void main(String[] args) throws Exception {  
    	// 需要加密的内容
        String content = "encryptContent";  
        // 密钥
        String key = "encryptKey";  
        
        String encrypt = encrypt(content, key);  
        System.out.println("加密后：" + encrypt);  
        
        String decrypt = decrypt(encrypt, key);  
        System.out.println("解密后：" + decrypt);  
    }  
    
      
    /** 
     * base 64 encode 
     * @param bytes 待编码的byte[] 
     * @return 编码后的base 64 code 
     */  
    private static String base64Encode(byte[] bytes){  
        return new BASE64Encoder().encode(bytes);  
    }  
      
    /** 
     * base 64 decode 
     * @param base64Code 待解码的base 64 code 
     * @return 解码后的byte[] 
     * @throws Exception 
     */  
    private static byte[] base64Decode(String base64Code) throws Exception{  
        return null == base64Code ? null : new BASE64Decoder().decodeBuffer(base64Code);  
    }  
    /** 
     * AES加密 
     * @param content 待加密的内容 
     * @param encryptKey 加密密钥 
     * @return 加密后的byte[] 
     * @throws Exception 
     */  
    private static byte[] aesEncryptToBytes(String content, String encryptKey) throws Exception {  
        KeyGenerator kgen = KeyGenerator.getInstance("AES");  
        kgen.init(128, new SecureRandom(encryptKey.getBytes()));  
  
        Cipher cipher = Cipher.getInstance("AES");  
        cipher.init(Cipher.ENCRYPT_MODE, new SecretKeySpec(kgen.generateKey().getEncoded(), "AES"));  
          
        return cipher.doFinal(content.getBytes("utf-8"));  
    }  
      
    /** 
     * AES加密为base 64 code 
     * @param content 待加密的内容 
     * @param encryptKey 加密密钥 
     * @return 加密后的base 64 code 
     * @throws Exception 
     */  
    public static String encrypt(String content, String encryptKey) throws Exception {  
        return base64Encode(aesEncryptToBytes(content, encryptKey));  
    }  
      
    /** 
     * AES解密 
     * @param encryptBytes 待解密的byte[] 
     * @param decryptKey 解密密钥 
     * @return 解密后的String 
     * @throws Exception 
     */  
    private static String aesDecryptByBytes(byte[] encryptBytes, String decryptKey) throws Exception {  
        KeyGenerator kgen = KeyGenerator.getInstance("AES");  
        kgen.init(128, new SecureRandom(decryptKey.getBytes()));  
          
        Cipher cipher = Cipher.getInstance("AES");  
        cipher.init(Cipher.DECRYPT_MODE, new SecretKeySpec(kgen.generateKey().getEncoded(), "AES"));  
        byte[] decryptBytes = cipher.doFinal(encryptBytes);  
          
        return new String(decryptBytes);  
    }  
      
    /** 
     * 将base 64 code AES解密 
     * @param encryptStr 待解密的base 64 code 
     * @param decryptKey 解密密钥 
     * @return 解密后的string 
     * @throws Exception 
     */  
    public static String decrypt(String encryptStr, String decryptKey) throws Exception {  
        return null == encryptStr ? null : aesDecryptByBytes(base64Decode(encryptStr), decryptKey);  
    }  
      
}  